Rapid advances in technological innovation over the past decade have transformed the average health care consumer into a buying agent with very high levels of expectation. Concurrent with this consumer trend is the trend in ever increasing health care costs and the regulatory push to contain them. Smaller, quicker, cheaper, more efficacious, and higher quality medical technologies are being sought to replace what have often been highly invasive, costly, and risky procedures in the past. In concert with this overall trend, physicians are seeking new and improved tools for gaining access to various organs and internal channels of the body with using the least invasive means possible. One such tool is the endoscope: a device used to examine and treat the interior of the body without making large incisions or without making an incision at all. Most procedures performed today using endoscopy were open surgical procedures until the equipment was developed to enable an endoscopic treatment.
An endoscope typically includes a shaft having endoscopic elements, such as imaging guides, light guides, or lumens (hollow channels) extending along its length. Contemporary fiber-based endoscopes utilize glass fibers for the imaging guides and light guides.
Current endoscopic technology is limited by a number of inherent weaknesses, which are seriously hampering the evolution in endoscopic evaluation and treatments. Some of the weaknesses associated with current endoscopes are directly linked to the use of glass fibers as endoscopic elements, and include the large size of the endoscopes, low durability, low flexibility, limited functionality, non-portability of reprocessing equipment, high cost of both the endoscope and the reprocessing equipment and, of critical importance, their non-disposability.
Large Size—A major limiting factor in many endoscopic procedures today is the size of the puncture or natural body opening, required to introduce the endoscope shaft. Reducing the size of the required opening makes it much easier on both the patient and the doctor. This also minimizes patient trauma and complications, thereby shortening the recovery time and reducing hospital cost.
Low Durability—Glass is crystalline, which makes it susceptible to fractures and breaks. Flexible glass imaging guides often have dark pixels (broken fibers) even when new; through use, more pixels go dark. Additionally, the fragile, complicated, multi-component construction of the rest of the endoscopic elements housed in the shaft and on the distal end often leads to other failures. Most breaks occur during procedures, which may cause complications, since the physician must switch endoscopes.
Low Flexibility—The bend radius of glass imaging guides is typically about three hundred times its diameter for repetitive bending. The bend radius of most materials is directly related to the size of that material. The larger diameter of the current endoscopes limits their flexibility (bend radius). High flexibility is required in many endoscopic procedures, such as examination of the biliary duct. Many applications would be easier to perform and new procedures realized by alleviating the bend limitations.
Limited Functionality—Most endoscopes are currently limited in what functions they may perform.
High Cost—Costs associated with the fabrication of an endoscope shaft are: the cost of imaging guides and light guides, the shaft housing cost, the cost of the other endoscopic elements, and the cost of assembling these components. A technology that would significantly lower cost would be very beneficial.
Non Disposable—The main reason endoscopes are not currently disposable is economic: they are just too expensive. Substantially reducing the cost of endoscopes, enabling the endoscope shaft to be disposable is desirable. There are numerous drawbacks associated with reusable endoscopes, which are described in the following paragraphs.
Patient-to-patient transfer of infections is a big problem with reusable endoscopes. There have been numerous reports and papers concerning patient-to-patient transfer of infections. In response, the CDC and FDA have issued a Public Health Advisory on this subject. An Apr. 8, 2002 article in USA Today has brought renewed public attention to this problem. The article cited and discussed several incidences of large-scale patient-to-patient transfer of infections and recent New York State Legislation action concerning endoscopes' safety.
Another problem with reusable endoscopes is staff exposure to hazardous chemicals. The chemicals used in reprocessing endoscopes, such as glutaraldehyde, may be extremely harmful to staff members. Regulations involved in working with these chemicals continue to grow more complex and elaborate.
Reusable endoscopes also have hidden costs, such as the long turnaround time between uses, and the corresponding effect on staff efficiency. Hidden costs include staff time, downtime between patients, endoscope repairs, backup endoscopes, chemicals, and cleaning equipment. These play a big part in the cost of endoscope ownership. Cleaning equipment may be difficult to operate, may not quite work right, and may leak cleaning fluid.
Repairs may be expensive on reusable endoscopes. Small flexible endoscopes break often (once during every ten procedures on average). Often the failures occur with the imaging guide (because of the fragile nature of the glass imaging guide) or other problems associated with the endoscopic elements housed in the shaft or on the distal end.
Another associated problem with reusable endoscopes is the non-portability of the components used to make the endoscopes reusable. Currently endoscopic use in the field (temporary military unit or remote hospital) is limited due to the size and the cost of equipment required to reprocess endoscopes between patients.
Reusable endoscopes also have a high cost of ownership; i.e. expense of breakage, maintenance, sterilization, risk of infection, etc. Cleaning chemicals are relatively expensive and the related equipment is very costly to purchase and maintain. For example, a STERRAD cleaning unit costs over a hundred thousand dollars to purchase. It is estimated that the cost (excluding capital equipment) of reprocessing an endoscope between patients to be $50-$150, depending on the type of endoscope.